Redox-active conjugated microporous anthraquinonylamine-based polymer network grafted with activated graphene toward high-performance flexible asymmetric supercapacitor electrodes

Abstract

Conjugated microporous polymer (CMP) networks with multi-dimensional structure and excellent physicochemical stability with tunable porosity are receiving increased interest. Herein, we report a composite of anthraquinonylamine-based CMP network and activated graphene (CMAP@AG hybrid) via facile Buchwald-Hartwig coupling. The hybrid composites are made via chemical grafting of CMAP onto AG samples prepared with varied activation treatment times. The grafting of CMAP with AG provides a good hybrid morphology, and its structural properties are tuned by controlling the activation step of AG since both porosity and flake size of the AG sample depend on the etching conditions. The optimized CMAP@AG hybrid exhibits a large surface area of 498 m2 g−1 and low sheet resistance of 278 Ω sq−1, and it can be directly used as an electrode material for supercapacitors. The CMAP@AG hybrid electrode shows a three-electrode specific capacitance of 751 F g−1 at a current density of 1 A g−1 with a good rate capability. A quasi-solid-state CMAP@AG//AG asymmetric supercapacitor (ASC) displays a high energy density of 76.6 Wh kg−1, a power density of 27,634 W kg−1, and good cycle stability with mechanical flexibility. These investigations offer insight into a rational design of CMP-based activated graphene composite for energy storage devices.